Scientists have scales to measure the strength of natural phenomena like earthquakes and hurricanes. But what about the eruptive power of volcanoes? For that, geologists use the Volcanic Explosivity Index. Here’s how it works.
250 million years ago, roughly 95% of the species on Earth went extinct in what's often called "the great dying." Megavolcanoes in Siberia were partly to blame. But what caused those volcanoes to erupt so powerfully, for centuries on end?